A Rapid, Near Patient System for Small Blood Volume Testing of Ammonia, Glutamine and Glutamate to Support Recurrent Monitoring of Acute Neonatal Hyperammonemia

ABSTRACT A RapidNear Patient System for Low Blood Volume Testing of AmmoniaGlutamine and Glutamate toSupport Recurrent Monitoring of Acute Neonatal HyperammonemiaSBIR Phase IIn newbornshyperammonemiaplasma ammonia andgtmol Lis often the first symptom of an underlying urea cycle disorderUCDfatty acid oxidation defect or severe liver diseaseand affects an estimatedinbirthsClinical symptoms may present as early as the first few days of life andwithout prompt medical attentioncan rapidly lead to serious brain injury or deathAcute treatment for hyperammonemia includes simultaneous diagnostic evaluation to distinguish the physiologic basis for ammonia accumulation and therapeutic interventions to reduce plasma ammonia levels and prevent permanent neurologic damageGiven the potential severity of symptoms and the rapid rate of disease progressionexpedited testing is vital to the survival of affected newbornsUnfortunatelydiagnostic testing for hyperammonemia is currently challenging in newborns due to the relatively large blood volumeandgtmLneeded for multiple analytesthe requirement for recurrent testing during therapy and technical limitations for ammonia assaysThere is a compelling need for better methods to rapidly diagnose and monitor hyperammonemia in newborns using low blood volumesWe propose to develop a novel digital microfluidic systemFINDERfor the rapidnear patient measurement of ammoniaglutamine and glutamate in newborns from very low volumes of whole bloodandltl for all assaysGlutamine and glutamate are critical for ammonia homeostasis and serve as useful biomarkers in certain UCDsThrough this Phase I SBIR projectwe will develop sensitiveautomated assays capable of measuring all three analytes withinminutesThe FINDER Hyperammonemia test panel will allow clinicians to perform repeated testing during acute treatment of blood volume limited neonates without increasing the risk for iatrogenic anemiaThe Phase I Specific Aims includedevelop novel enzymatic assays for ammoniaglutamine and glutamate measurement using the FINDER digital microfluidic cartridgeoptimize assay conditions and determine preliminary analytical sensitivity and specificityandfeasibility demonstration using patient plasma samplesThe key milestone for progression to Phase II will be the successful demonstration of all assays on cartridge with acceptable sensitivity and precisionIn future Phase II effortswe will expand the panel to include additional analytesketonesglucose and or liver function testsestablish reagent drying protocols for the multiplexed assay and perform full analytical and clinical validationsWe will seek FDA approval of the final productwhich will initially be marketed for use in newborn patients in U Shospitalswith a potential future market towards older patients with known metabolic disorderswho may benefit from the rapidlow blood volume features of the platform PROJECT NARRATIVE Neonatal hyperammonemia caused by elevated blood ammonia levels is often indicative of a metabolic disorder and leads to devastating neurological effects or death if not detected and treated in a timely mannerMeasurement of plasma ammoniaglutamine and glutamate is indicated only after the presentation of symptomsand general chemistry laboratories in smaller hospitals or underdeveloped areas countries are often not equipped with the necessary equipment to measure ammonia or plasma amino acid levelsGiven the severity of symptomsearly detection and treatment of hyperammonemia is vital to the survival of affected newbornsThere is a compelling need for a near patient testing platform to quickly identify newborns with elevated ammonia levelsand for recurrent monitoring of ammoniaglutamine and glutamate levels during acute disease treatment